Abnormal Calcium Levels During Trauma Resuscitation Are Associated With Increased Mortality, Increased Blood Product Use, and Greater Hospital Resource Consumption: A Pilot Investigation

Prevalence and outcomes of hypocalcemia on ED arrival in traumatic patients before blood transfusions: a systematic review and meta-analysis

BACKGROUND

Hypocalcemia represents a critical physiological disturbance in trauma-related hemorrhagic shock patients. Nonetheless, the prevalence and effects of hypocalcemia remain uncertain. This study aims to explore the prevalence of hypocalcemia before blood transfusions and its related mortality in adult patients with major traumatic injuries.

METHOD

We conducted a systematic search through databases, including PubMed, EMBASE, Scopus, and Web of Science, from their inception until June 30, 2024. Patients with major traumatic injuries whose serum calcium was measured upon arrival at the emergency department (ED) were included. We excluded those with prior blood transfusions, pre-clinical studies, review articles, and studies without a control group. Meta-analysis using a random-effect model was performed. Heterogeneity was evaluated using Cochrane Q and I² statistics. The study's risk of bias was assessed using the Joanna Briggs Institute's critical appraisal checklist. Publication bias was assessed using Egger's test and contour funnel plot visualization.

RESULTS

Of the total, 1,984 abstracts were screened, leading to 15 studies in this review and meta-analysis. The overall prevalence of hypocalcemia upon ED arrival was 56% (95% CI 37%-74%), with high heterogeneity (I2 99.8%) observed. Hypocalcemia patients also had higher mortality rates than normocalcemia patients (OR 2.44, 95% CI 1.76-3.40).

CONCLUSION

Hypocalcemia on ED arrival is common among adult trauma patients, who also exhibit a notably high mortality rate within this demographic. We recommend the monitoring of ionized calcium levels in traumatic adult patients. Furthermore, systematically designed studies examining the optimal thresholds, treatment protocols, and outcomes should be prioritized as the focal point of research.

TRIAL REGISTRATION

CRD42024549054 ( http://www.crd.york.ac.uk/PROSPERO ).

The Association of Calcium Derangements With 24-Hour Outcomes in the Deployed Combat Setting

INTRODUCTION

Calcium derangements remain poorly characterized in the combat trauma population. We describe the incidence of emergency department (ED) calcium derangements, associated physiologic derangements, and 24-hour mortality from the deployed combat setting.

MATERIALS AND METHODS

We analyzed adult casualties from 2007 to 2023 from the DoD Trauma Registry for U.S. military, U.S. contractor, and coalition casualties that had at least 1 ionized calcium value documented in the ED at a Role 2 or Role 3 military treatment facility. We constructed a series of multivariable logistic regression models to test for the association of hypocalcemia and hypercalcemia with physiological derangements, blood product consumption, and survival. Vital signs and other laboratory studies were based on the concurrent ED encounter.

RESULTS

There were 941 casualties that met inclusion for this analysis with 26% (245) having at least 1 calcium derangement. Among those, 22% (211) had at least 1 episode of hypocalcemia and 5% (43) had at least 1 episode of hypercalcemia in the ED. The vast majority (97%, 917) received calcium at least once. Median composite injury severity scores were lower among those with no calcium derangement (8 versus 17, P < .001). Survival was higher during the total hospitalization (98% versus 93%) among those with calcium derangements but similar at 24 hours (99% versus 98%, P = .059). After adjusting for confounder, any hypocalcemic measurement was associated with an elevated international normalized ratio (odds ratio 1.94, 95% CI 1.19-3.16), acidosis (1.66, 1.17-2.37), tachycardia (2.11, 1.42-3.15), hypotension (1.92, 1.09-3.38), depressed Glasgow coma scale (3.20, 2.13-4.81), elevated shock index (2.19, 1.45-3.31), submassive transfusion (3.97, 2.60-6.05), massive transfusion (4.22, 2.66-6.70), supermassive transfusion (3.65, 2.07-6.43), and all hospital stay mortality (2.30, 1.00-5.29). Comparatively, any hypercalcemic measurement was associated with acidosis (2.96, 1.39-6.32), depressed Glasgow coma scale (4.28, 1.81-10.13), submassive transfusion (3.40, 1.37-8.43), massive transfusion (6.25, 2.63-14.83), and supermassive transfusion (13.00, 5.47-30.85).

CONCLUSIONS

Both hypocalcemia and hypercalcemia in the ED were associated with physiological derangements and blood product use, with a greater extent observed in those with hypocalcemia compared to those with hypercalcemia. Prospective studies are underway to better explain and validate these findings.

Ionised calcium levels during trauma resuscitation in predicting outcomes-a prospective cohort study

BACKGROUND

Haemorrhage remains the leading cause of preventable mortality following trauma, often aggravated by the acidosis, hypothermia and coagulopathy-the lethal triad of trauma. However, the impact of trauma-induced hypocalcemia on the haemorrhage remains unclear. It is intuitive to consider perturbations of ionised calcium early during trauma resuscitation in acutely injured patients given its pathophysiological significance for an improved outcome. Thus, we conducted a prospective study to analyse the role of ionized calcium ion levels during trauma resuscitation and its association with the need for blood transfusion(s) requirement and mortality.

METHODS

A prospective study was conducted on acutely injured patients with haemorrhage getting admitted to a Level 1 trauma center in India between September 2020 and June 2022. Ionised calcium was measured on arrival, after 6 h, and on day two of the injury to assess the prevalence. The amount of blood transfusion received by the patient was noted along with other demographic and in-hospital details. The association of hypocalcemia with blood transfusion and mortality was also evaluated.

RESULTS

Of the 1961 patients screened for eligibility, 200 patients were recruited and analysed. 72.5% of patients were hypocalcaemic on emergency department (ED) admission. Ionized hypocalcaemia was significantly associated with the need for blood transfusion(s) (p-value < 0.01). A significant association was also noted between ionized hypocalcaemia and mortality (p-value: 0.0085). On the univariate and multivariable analysis, ionized hypocalcaemia was a significant predictor of mortality.

CONCLUSIONS

Ionized hypocalcaemia is widely prevalent among acutely injured. Trauma-induced hypocalcaemia at admission is associated with increased need for blood transfusions and increased mortality.

Comparison of the lethal triad and the lethal diamond in severe trauma patients: a multicenter cohort

BACKGROUND

To reduce the number of deaths caused by exsanguination, the initial management of severe trauma aims to prevent, if not limit, the lethal triad, which consists of acidosis, coagulopathy, and hypothermia. Recently, several studies have suggested adding hypocalcemia to the lethal triad to form the lethal diamond, but the evidence supporting this change is limited. Therefore, the aim of this study was to compare the lethal triad and lethal diamond for their respective associations with 24-h mortality in severe trauma patients receiving transfusion.

METHODS

We performed a multicenter retrospective analysis of patients in TraumaBase®, a French database (2011-2023). The patients included in this study were all trauma patients who had received transfusions of at least 1 unit of red blood cells (RBCs) within the first 6 h of hospital admission and for whom ionized calcium measurements were available. Hypocalcemia was defined as an ionized calcium level < 1.1 mmol/L.

RESULTS

A total of 2141 severe trauma patients were included (median age: 39, interquartile range [IQR]: 26-57; median injury severity score: 27, IQR: 17-41). Patients primarily presented with blunt trauma (81.7%), and a 24-h mortality rate of 16.1% was observed. Receiver operating characteristic curve analysis revealed no significant difference in the association with 24-h mortality between the lethal diamond (area under the curve [AUC]: 0.71) and the lethal triad (AUC: 0.72) (p = 0.26). The strength of the association with 24-h mortality was similar between the lethal triad and the lethal diamond, with Cramer's V values of 0.29 and 0.28, respectively.

CONCLUSIONS

This study revealed no significant difference between the lethal triad and the lethal diamond in terms of their respective associations with 24-h mortality in severe trauma patients requiring transfusion. These results raise questions about the independent role of hypocalcemia in early mortality.

Higher Doses of Calcium Associated With Survival in Trauma Patients

INTRODUCTION

Calcium is required for coagulation, cardiac output, and peripheral vascular resistance. Between 85% and 94% of trauma patients treated with massive blood transfusion develop hypocalcemia.1 The aim of this study is to evaluate the relationship between increased intravenous calcium administration during massive transfusion and improved survival of trauma patients.

METHODS

We performed a retrospective analysis of trauma patients who received massive transfusion over a 2-y period. Doses of elemental calcium administered per unit of blood product transfused were calculated by calcium to blood product ratio (CBR). Chi-square test evaluated association between coagulopathy and 30-d mortality. Two-sample t-test evaluated association between CBR and coagulopathy. Bivariate regression analysis evaluated association between CBR and blood products transfused per patient. Multivariable logistic regression analysis, controlling for age, sex, coagulopathy, and Injury Severity Score evaluated the association between CBR and mortality.

RESULTS

The study included 77 patients. Coagulopathy was associated with increased 30-d mortality (P < 0.05). Patients who survived had higher CBR than those who died (P < 0.05). CBR was associated with a significant reduction in total blood products transfused per patient (P < 0.05). CBR was not associated with coagulopathy (P = 0.24). Multivariable logistic regression analysis demonstrated that Injury Severity Score ≥16, coagulopathy and decreased CBR were significant predictors of mortality (P < 0.05). CBR above 50 mg was a predictor of survival (P < 0.05).

CONCLUSIONS

Higher doses of calcium given per blood product transfused were associated with improved 30-d survival and decreased blood product transfusions.

Ratios of calcium to citrate administration in blood transfusion for traumatic hemorrhage: A retrospective cohort study

BACKGROUND

Massive transfusion with citrated blood products causes hypocalcemia, which is associated with mortality. Recognition of this problem has led to increased calcium administration; however, the optimal dosing is still unknown.

STUDY DESIGN AND METHODS

This retrospective, single-center study included level 1 trauma patients in 2019 and 2020 who underwent an operation within 12 h of arrival and received a transfusion. Preoperative and intraoperative administrations were totaled to calculate the ratio of administered calcium to the number of blood transfusions for each patient. The citrate content of each blood component was estimated to calculate a second ratio, the ratio of administered calcium to administered citrate. Receiver Operating Characteristic (ROC) curves were performed on both ratios to determine the optimal cutoff values for predicting severe hypocalcemia (ionized calcium <0.9 mmol/L) and hypercalcemia (>1.35 mmol/L) at the end of the intraoperative period.

RESULTS

A total of 506 trauma activations were included, receiving a mean of 17.4 citrated blood products and 16.3 mmol of calcium (equivalent to 2400 mg of calcium chloride). No ratio was statistically significant in differentiating severely hypocalcemic patients from the rest. A calcium to blood ratio of 0.903 mmol of administered calcium per citrated blood product differentiated hypercalcemic patients from the rest.

DISCUSSION

Quantifying received calcium and citrated blood products was insufficient to predict severe hypocalcemia, suggesting other contributions to hypocalcemia. We demonstrated an upper-limit ratio for calcium administration in traumatic hemorrhage; however, further studies are required to determine what calcium dosing regimen results in the best outcomes.

Electrolyte Imbalance in Acute Traumatic Brain Injury: Insights from the First 24 h

BACKGROUND/OBJECTIVES

Electrolyte disturbances are common in patients with traumatic brain injury (TBI), particularly affecting sodium, potassium, chloride, and calcium levels. This study aims to provide insights into these disturbances within the first 24 h post-injury.

METHODS

We conducted a cross-sectional analysis of 50 TBI patients, excluding those with conditions affecting electrolyte balance. Electrolyte levels were measured, and correlations with demographic data, trauma mechanisms, imaging findings, and Glasgow Coma Scale (GCS) scores were analyzed.

RESULTS

The results indicated that chloride levels inversely correlated with GCS scores (ρ = -0.515; p = 0.002), suggesting that elevated chloride may indicate severe neurological impairment. Potassium levels were significantly associated with subdural hematoma (p = 0.032) and subarachnoid hemorrhage (p = 0.043), highlighting their potential as markers for severe brain injuries. No significant associations were found between sodium or calcium levels and the studied variables.

CONCLUSIONS

These findings underscore the importance of early monitoring of chloride and potassium levels in TBI patients to improve management and outcomes. Future research should focus on larger, multi-center studies to validate these findings and develop comprehensive guidelines for managing electrolyte imbalances in TBI patients.

Impact of a calcium replacement protocol during massive transfusion in trauma patients at a level 2 trauma center

PURPOSE

Hypocalcemia is associated with increased mortality in trauma patients with hemorrhagic shock who require massive transfusion protocols (MTPs). Despite known risks of potentiating hypocalcemia with blood product administration, there is little research discussing appropriate calcium replacement. The purpose of this study was to evaluate the ability of a standardized calcium replacement protocol to reduce the incidence of hypocalcemia in trauma patients undergoing MTP.

METHODS

This retrospective, single-center, pre-post study evaluated the use of a calcium replacement protocol during MTP. Adult trauma patients with MTP orders who received at least one "round" of product transfusion were included. Patients were excluded if their ionized calcium (iCa) levels were unavailable or they were transferred to a higher level of care within 4 hours of presentation. The primary outcome was incidence of hypocalcemia (iCa of <1.1 mg/dL) within 24 hours of MTP initiation. Secondary endpoints included the incidence of severe hypocalcemia (iCa of <0.9 mg/dL), time to first calcium dose, total calcium dose administered (mEq), resolution of hypocalcemia within 24 hours, hypercalcemia, adherence to the calcium replacement protocol, and mortality.

RESULTS

The incidence of hypocalcemia within 24 hours was significantly lower in the postprotocol group (63% vs 95.2%; P = 0.006). There was not a significant difference in the incidence of severe hypocalcemia between the groups (39.1% vs 69.1%; P = 0.083). Time to first calcium dose was significantly shorter in postprotocol patients compared to preprotocol patients (median [interquartile range], 5.5 [0-21] minutes vs 43 [22.8-73] minutes; P < 0.0001), and postprotocol patients were administered more calcium during MTP (40.8 [27.2-54.4] mEq vs 27.2 [14-32.2] mEq; P = 0.005). Adherence to the protocol was seen in only 37% of patients in the postprotocol group. There was no difference in the rate of adverse events or overall mortality.

CONCLUSION

Trauma patients who received massive transfusion of blood products had a significantly lower incidence of hypocalcemia after a calcium replacement protocol was implemented.

Impact of hypocalcemia on mortality in pediatric trauma patients who require transfusion

BACKGROUND

Admission hypocalcemia has been associated with poor outcomes in injured adults. The impact of hypocalcemia on mortality has not been widely studied in pediatric trauma.

METHODS

A pediatric trauma center database was queried retrospectively (2013-2022) for children younger than 18 years who received blood transfusion within 24 hours of injury and had ionized calcium (iCal) level on admission. Children who received massive transfusion (>40 mL/kg) prior to hospital arrival or calcium prior to laboratory testing were excluded. Hypocalcemia was defined by the laboratory lower limit (iCal <1.00). Main outcomes were in-hospital mortality and 24-hour blood product requirements. Logistic regression analysis was performed to adjust for Injury Severity Score (ISS), admission shock index, Glasgow Coma Scale (GCS) score, and weight-adjusted total transfusion volume.

RESULTS

In total, 331 children with median (IQR) age of 7 years (2-3 years) and median (IQR) ISS 25 (14-33) were included, 32 (10%) of whom were hypocalcemic on arrival to the hospital. The hypocalcemic cohort had higher ISS (median (IQR) 30(24-36) vs. 22 (13-30)) and lower admission GCS score (median (IQR) 3 (3-12) vs. 8 (3-15)). Age, sex, race, and mechanism were not significantly different between groups. On univariate analysis, hypocalcemia was associated with increased in-hospital (56% vs. 18%; p < 0.001) and 24-hour (28% vs. 5%; p < 0.001) mortality. Children who were hypocalcemic received a median (IQR) of 22 mL/kg (7-38) more in total weight-adjusted 24-hour blood product transfusion following admission compared to the normocalcemic cohort ( p = 0.005). After adjusting for ISS, shock index, GCS score, and total transfusion volume, hypocalcemia remained independently associated with increased 24-hour (odds ratio, 4.93; 95% confidence interval, 1.77-13.77; p = 0.002) and in-hospital mortality (odds ratio, 3.41; 95% confidence interval, 1.22-9.51; p = 0.019).

CONCLUSION

Hypocalcemia is independently associated with mortality and receipt of greater weight-adjusted volumes of blood product transfusion after injury in children. The benefit of timely calcium administration in pediatric trauma needs further exploration.

LEVEL OF EVIDENCE

Prognostic and Epidemiological; Level III.

Hypocalcaemia upon arrival (HUA) in trauma patients who did and did not receive prehospital blood products: a systematic review and meta-analysis

PURPOSE

Hypocalcaemia upon arrival (HUA) to hospital is associated with morbidity and mortality in the trauma patient. It has been hypothesised that there is an increased incidence of HUA in patients receiving prehospital transfusion as a result of citrated blood products. This research aimed to determine if there was a difference in arrival ionised calcium (iCa) levels in trauma patients who did and did not receive prehospital transfusion.

METHODS

We conducted a systematic review and meta-analysis of patients with an Injury Severity Score (ISS) > / = 15 and an iCa measured on hospital arrival. We then derived mean iCa levels and attempted to compare between-group variables across multiple study cohorts.

RESULTS

Nine studies reported iCa on arrival to ED, with a mean of 1.08 mmol/L (95% CI 1.02-1.13; I2 = 99%; 2087 patients). Subgroup analysis of patients who did not receive prehospital transfusion had a mean iCa of 1.07 mmol/L (95% CI 1.01-1.14; I2 = 99%, 1661 patients). Transfused patients in the 3 comparative studies had a slightly lower iCa on arrival compared to those who did not receive transfusion (mean difference - 0.03 mmol/L, 95% CI - 0.04 to - 0.03, I2 = 0%, p = 0.001, 561 patients).

CONCLUSION

HUA is common amongst trauma patients irrespective of transfusion. Transfused patients had a slightly lower initial iCa than those without transfusion, though the clinical impact of this remains to be clarified. These findings question the paradigm of citrate-induced hypocalcaemia alone in trauma. There is a need for consensus for the definition of hypocalcaemia to provide a basis for future research into the role of calcium supplementation in trauma.

Calcium supplementation during trauma resuscitation: a propensity score-matched analysis from the TraumaRegister DGU®

BACKGROUND

In major trauma patients, hypocalcemia is associated with increased mortality. Despite the absence of strong evidence on causality, early calcium supplementation has been recommended. This study investigates whether calcium supplementation during trauma resuscitation provides a survival benefit.

METHODS

We conducted a retrospective analysis using data from the TraumaRegister DGU® (2015-2019), applying propensity score matching to balance demographics, injury severity, and management between major trauma patients with and without calcium supplementation. 6 h mortality, 24 h mortality, and in-hospital mortality were considered as primary outcome parameters.

RESULTS

Within a cohort of 28,323 directly admitted adult major trauma patients at a European trauma center, 1593 (5.6%) received calcium supplementation. Using multivariable logistic regression to generate propensity scores, two comparable groups of 1447 patients could be matched. No significant difference in early mortality (6 h and 24 h) was observed, while in-hospital mortality appeared higher in those with calcium supplementation (28.3% vs. 24.5%, P = 0.020), although this was not significant when adjusted for predicted mortality (P = 0.244).

CONCLUSION

In this matched cohort, no evidence was found for or against a survival benefit from calcium supplementation during trauma resuscitation. Further research should focus on understanding the dynamics and kinetics of ionized calcium levels in major trauma patients and identify if specific conditions or subgroups could benefit from calcium supplementation.

Direct red blood cell effect on thrombosis is dependent on the interaction of tissue factor and calcium with membrane phosphatidylserine

BACKGROUND

Prior literature has implicated red blood cells (RBCs) in the initiation of thrombosis and suggests that posttransfusion hypercoagulability may occur secondary to the effects of RBCs. Elevated serum tissue factor is a known sequelae of acute trauma. Phosphatidylserine (PS) is a prothrombotic phospholipid present within the RBC cell membrane. We hypothesized that RBC aggregation is dependent on the interaction between RBC membrane bound (exposed) PS, extracellular calcium, and tissue factor.

METHODS

Human whole blood (WB) was separated into components, including RBCs and platelet-rich plasma (PRP). Whole blood, PRP, and RBCs underwent impedance aggregometry utilizing arachidonic acid (AA), ADP, collagen, calcium, and tissue factor (TF)-based agonists. Red blood cells then underwent impedance aggregometry utilizing combined calcium and TF agonists. Red blood cells were pretreated with Annexin V, a known PS blocking agent, and underwent impedance aggregometry with combined calcium and TF agonists to determine if the mechanism of calcium/TF-induced RBC aggregability is dependent on PS. Red blood cells treated with calcium, TF, calcium+TF, and pre-treated with Annexin V followed by calcium+TF were perfused through an in vitro model of pulmonary microcirculatory flow.

RESULTS

Red blood cell aggregation was significantly higher than that of WB and PRP when utilizing a TF agonist, an effect unique to TF. The combination of calcium and TF demonstrated significantly higher RBC aggregation than either agonist alone. Pretreatment with Annexin V resulted in a significantly reduced aggregability of RBC following treatment with TF + calcium. Red blood cells aged to 42 days did not exhibit significant change in aggregation. Exposure to calcium and TF significantly reduced time to thrombosis of RBCs perfused through a pulmonary microcirculatory model.

CONCLUSION

Treatment with both TF and calcium synergistically induces RBC aggregation. Phosphatidylserine appears to play an integral role in the TF/calcium-based, age-independent RBC aggregation response. Red blood cells treated with TF + calcium exhibit more rapid thrombus formation in an in vitro model of pulmonary microcirculatory perfusion.

Maintaining a whole blood-centered transfusion improves survival in hemorrhagic resuscitation

BACKGROUND

Whole blood (WB) transfusion has been shown to improve mortality in trauma resuscitation. The optimal ratio of packed red blood cells (pRBC) to WB in emergent transfusion has not been determined. We hypothesized that a low pRBC/WB transfusion ratio is associated with improved survival in trauma patients.

METHODS

We analyzed the 2021 Trauma Quality Improvement Program (TQIP) database to identify patients who underwent emergent surgery for hemorrhage control and were transfused within 4 hours of hospital arrival, excluding transfers or deaths in the emergency department. We stratified patients based on pRBC/WB ratios. The primary outcome was mortality at 24 hours. Logistic regression was performed to estimate odds of mortality among ratio groups compared with WB alone, adjusting for injury severity, time to intervention, and demographics.

RESULTS

Our cohort included 17,562 patients; of those, 13,678 patients had only pRBC transfused and were excluded. Fresh frozen plasma/pRBC ratio was balanced in all groups. Among those who received WB (n = 3,884), there was a significant increase in 24-hour mortality with higher pRBC/WB ratios (WB alone 5.2%, 1:1 10.9%, 2:1 11.8%, 3:1 14.9%, 4:1 20.9%, 5:1 34.1%, p = 0.0001). Using empirical cutpoint estimation, we identified a 3:1 ratio or less as an optimal cutoff point. Adjusted odds ratios of 24-hour mortality for 4:1 and 5:1 groups were 2.85 (95% confidence interval [CI], 1.19-6.81) and 2.89 (95% CI, 1.29-6.49), respectively. Adjusted hazard ratios of 24-hour mortality were 2.83 (95% CI, 1.18-6.77) for 3:1 ratio, 3.67 (95% CI, 1.57-8.57) for 4:1 ratio, and 1.97 (95% CI, 0.91-4.23) for 5:1 ratio.

CONCLUSION

Our analysis shows that higher pRBC/WB ratios at 4 hours diminished survival benefits of WB in trauma resuscitation. Further efforts should emphasize this relationship to optimize trauma resuscitation protocols.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level III.

Severe hypocalcemia at admission is associated with increased transfusion requirements: A retrospective study in a level 1 trauma center

INTRODUCTION

In recent years, hypocalcemia has been added to the "lethal triad" of the trauma patient, thus constituting the "lethal diamond". Nevertheless, its proper role remains debated. The aim of this study is to evaluate the association between severe hypocalcemia at admission and 24 h- transfusion requirements in severe trauma patients in a level 1 trauma center.

STUDY DESIGN AND METHODS

In a monocentric retrospective observational study from January 2015 to May 2021, 137 traumatized adult patients transfused within 24 h after hospital admission was included in the study. The threshold for severe hypo ionized calcemia was ≤ 0.9 mmol/L.

RESULTS

137 patients were included in the study, 23 presented with severe hypo-iCa at admission, 111 moderate hypo-iCa (0.9-1.2 mmol/L) and 3 normal iCa (≥ 1.2 mmol/L). Patients with severe hypo-iCa at admission had higher severity scores (SAPSII 58 IQR [51-70] vs. 45 IQR [32-56]; p = 0.001 and ISS 34 IQR [26-39] vs. 26 IQR [17-34]; p = 0.003). 24 h-transfusion requirements were greater for patients with severe hypo-iCa, regardless of the type of blood products transfused. There was a significant negative correlation between admission iCa and 24 h-transfusion (r = -0.45, p < 0.001). The difference in mortality was not significant between the two groups (24 h mortality: 17 % (4/23) for severe hypo-iCa vs. 8 % (9/114) for non-severe hypo-iCa; p = 0.3).

DISCUSSION

This study highlights the high prevalence of severe hypocalcemia in trauma patients and its association with increased 24 h- transfusion requirements.

Analysis of risk factors for trauma-induced coagulopathy in elderly major trauma patients

BACKGROUND

Trauma-induced coagulopathy (TIC) due to serious injuries significantly leads to increased mortality and morbidity among elderly patients. However, the risk factors of TIC are not well elucidated. This study aimed to explore the risk factors of TIC in elderly patients who have major trauma.

METHODS

In this retrospective study, the risk factors for TIC in elderly trauma patients at a single trauma center were investigated between January 2015 and September 2020. The demographic information including gender, age, trauma parts, injury severity, use of blood products, use of vasopressors, need of emergency surgery, duration of mechanical ventilation, length of stay in the intensive care unit (ICU) and hospital, and clinical outcomes were extracted from electric medical records. Multivariate logistic regression analysis was performed to differentiate risk factors, and the performance of the model was evaluated using receiver operating characteristics (ROC) curves.

RESULTS

Among the 371 elderly trauma patients, 248 (66.8%) were male, with the age of 72.5 ± 6.8 years, median injury severity score (ISS) of 24 (IQR: 17-29), and Glasgow coma score (GCS) of 14 (IQR: 7-15). Of these patients, 129 (34.8%) were diagnosed with TIC, whereas 242 (65.2%) were diagnosed with non-TIC. The severity scores such as ISS (25 [20-34] vs. 21 [16-29], P<0.001) and shock index (SI), (0.90±0.66 vs. 0.58 ± 0.18, P<0.001) was significantly higher in the TIC group than in the non-TIC group. Serum calcium levels (1.97±0.19 mmol/L vs. 2.15±0.16 mmol/L, P<0.001), fibrinogen levels (1.7±0.8 g/L vs. 2.8±0.9 g/L, P<0.001), and base excess (BE, -4.9±4.6 mmol/L vs. -1.2 ± 3.1 mmol/L, P<0.001) were significantly lower in the TIC group than in the non-TIC group. Multivariate logistic regression analysis revealed that ISS>16 (OR: 3.404, 95%CI: 1.471-7.880; P=0.004), SI>1 (OR: 5.641, 95%CI: 1.700-18.719; P=0.005), low BE (OR: 0.868, 95%CI: 0.760-0.991; P=0.037), hypocalcemia (OR: 0.060, 95%CI: 0.009-0.392; P=0.003), and hypofibrinogenemia (OR: 0.266, 95%CI: 0.168-0.419; P<0.001) were independent risk factors for TIC in elderly trauma patients. The AUC of the prediction model included all these risk factors was 0.887 (95%CI: 0.851-0.923) with a sensitivity and specificity of 83.6% and 82.6%, respectively.

CONCLUSION

Higher ISS (more than 16), higher SI (more than 1), acidosis, hypocalcemia, and hypofibrinogenemia emerged as independent risk factors for TIC in elderly trauma patients.

Factors Associated With Early Discharge in Pediatric Trauma Patients Transported by Rotor: A Retrospective Analysis

OBJECTIVE

Helicopter emergency medical services (HEMS) play a crucial role in providing timely transport for pediatric trauma patients. This service carries the highest risk of any mode of medical transport and a high financial burden, and patient outcomes are seldom investigated. This study evaluated the characteristics of pediatric trauma patients discharged within 24 hours after transport by HEMS.

METHODS

This was a single-center, retrospective analysis on pediatric trauma patients transported by HEMS from 2019 to 2022. Analyses were performed to identify factors associated with discharge within 24 hours. Factors analyzed included vital signs, Shock Index, Pediatric Age-Adjusted scores, management details, and clinical outcomes.

RESULTS

A total of 466 pediatric trauma patients were transported by HEMS, including 171 patients (36.7%) who were discharged within 24 hours. There were no differences in the rates of blunt and penetrating injury (P = .583). Patients discharged within 24 hours were more likely to have a higher Glasgow Coma Scale score (14 vs. 11, P < .001) and a lower Injury Severity Score (4.9 vs. 14.7, P < .001), required less prehospital fluid resuscitation (5.5 vs. 11.7 mL/kg, P = .039), and had higher levels of serum calcium (9.3 vs. 8.9 mg/dL, P < .001). They were also less likely to meet criteria for level 1 trauma activation (13.0% vs. 40%, P < .001) or to require prehospital respiratory support of any kind (4.1% vs. 31.1%, P < .001). After arrival at the hospital, they were less likely to require blood transfusions (2.9% vs. 29.8%, P < .001) or tranexamic acid (2.9% vs. 11.5%, P = .001).

CONCLUSION

Trauma patients with a high Glasgow Coma Scale score and a low Injury Severity Score who do not require critical care or meet the criteria for high-level trauma activation may be suitable for transportation with lower acuity. Further studies aimed at improving triage and implementing improved criteria for the use of HEMS are paramount.

EVALUATION OF TRANEXAMIC ACID AND CALCIUM CHLORIDE IN MAJOR TRAUMAS IN A PREHOSPITAL SETTING: A NARRATIVE REVIEW

ABSTRACT

Excessive blood loss in the prehospital setting poses a significant challenge and is one of the leading causes of death in the United States. In response, emergency medical services (EMS) have increasingly adopted the use of tranexamic acid (TXA) and calcium chloride (CaCl 2 ) as therapeutic interventions for hemorrhagic traumas. Tranexamic acid functions by inhibiting plasmin formation and restoring hemostatic balance, while calcium plays a pivotal role in the coagulation cascade, facilitating the conversion of factor X to factor Xa and prothrombin to thrombin. Despite the growing utilization of TXA and CaCl 2 in both prehospital and hospital environments, a lack of literature exists regarding the comparative effectiveness of these agents in reducing hemorrhage and improving patient outcomes. Notably, Morgan County Indiana EMS recently integrated the administration of TXA with CaCl 2 into their treatment protocols, offering a valuable opportunity to gather insight and formulate updated guidelines based on patient-centered outcomes. This narrative review aims to comprehensively evaluate the existing evidence concerning the administration of TXA and CaCl 2 in the prehospital management of hemorrhages, while also incorporating and analyzing data derived from the co-administration of these medications within the practices of Morgan County EMS. This represents the inaugural description of the concurrent use of both TXA and CaCl 2 to manage hemorrhages in the scientific literature.

Trauma-induced disturbances in ionized calcium levels correlate parabolically with coagulopathy, transfusion, and mortality: a multicentre cohort analysis from the TraumaRegister DGU®

BACKGROUND

To which extent trauma- induced disturbances in ionized calcium (iCa2+) levels have a linear relationship with adverse outcomes remains controversial. The goal of this study was to determine the association between the distribution and accompanying characteristics of transfusion-independent iCa2+ levels versus outcome in a large cohort of major trauma patients upon arrival at the emergency department.

METHODS

A retrospective observational analysis of the TraumaRegister DGU® (2015-2019) was performed. Adult major trauma patients with direct admission to a European trauma centre were selected as the study cohort. Mortality at 6 h and 24 h, in-hospital mortality, coagulopathy, and need for transfusion were considered as relevant outcome parameters. The distribution of iCa2+ levels upon arrival at the emergency department was calculated in relation to these outcome parameters. Multivariable logistic regression analysis was performed to determine independent associations.

RESULTS

In the TraumaRegister DGU® 30 183 adult major trauma patients were found eligible for inclusion. iCa2+ disturbances affected 16.4% of patients, with hypocalcemia (< 1.10 mmol/l) being more frequent (13.2%) compared to hypercalcemia (≥ 1.30 mmol/l, 3.2%). Patients with hypo- and hypercalcemia were both more likely (P < .001) to have severe injury, shock, acidosis, coagulopathy, transfusion requirement, and haemorrhage as cause of death. Moreover, both groups had significant lower survival rates. All these findings were most distinct in hypercalcemic patients. When adjusting for potential confounders, mortality at 6 h was independently associated with iCa2+ < 0.90 mmol/L (OR 2.69, 95% CI 1.67-4.34; P < .001), iCa2+ 1.30-1.39 mmol/L (OR 1.56, 95% CI 1.04-2.32, P = 0.030), and iCa2+  ≥ 1.40 mmol/L (OR 2.87, 95% CI 1.57-5.26; P < .001). Moreover, an independent relationship was determined for iCa2+ 1.00-1.09 mmol/L with mortality at 24 h (OR 1.25, 95% CI 1.05-1.48; P = .0011), and with in-hospital mortality (OR 1.29, 95% CI 1.13-1.47; P < .001). Both hypocalcemia < 1.10 mmol/L and hypercalcemia ≥ 1.30 mmol/L had an independent association with coagulopathy and transfusion.

CONCLUSIONS

Transfusion-independent iCa2+ levels in major trauma patients upon arrival at the emergency department have a parabolic relationship with coagulopathy, need for transfusion, and mortality. Further research is needed to confirm whether iCa2+ levels change dynamically and are more a reflection of severity of injury and accompanying physiological derangements, rather than an individual parameter that needs to be corrected as such.

Effect of ionized calcium level on short-term prognosis in severe multiple trauma patients: a clinical study

Background

Hypocalcemia has been reported as an independent predictor of trauma mortality. We investigated the relationship between temporal variations in blood ionized calcium concentration (iCa) and prognosis in severe trauma patients who underwent massive transfusion protocol (MTP).

Methods

This single-center, retrospective, observational study investigated 117 severe trauma patients treated with MTP in the Department of Emergency Medicine and Critical Care, Saitama Medical Center, Saitama Medical University, between March 2013 and March 2019. Multivariate logistic regression analysis was performed, assigning pH-corrected initial and minimum blood ionized calcium concentration within 24 hours of admission (iCa_min), age, initial systolic blood pressure and Glasgow Coma Scale (GCS) score, and incidence of Ca supplementation as independent variables and 28-day mortality as dependent variable.

Results

The logistic regression analysis identified iCa_min (adjusted OR 0.03, 95% CI 0.002 to 0.4), age (adjusted OR 1.05, 95% CI 1.02 to 1.09), and GCS score (adjusted OR 0.84, 95% CI 0.74 to 0.94) as significant independent predictors of 28-day mortality. The receiver operating characteristic analysis identified optimal cut-off value of iCa_min for predicting 28-day mortality as 0.95 mmoL/L (area under the curve 0.74).

Conclusion

In the management of patients with traumatic hemorrhagic shock, aggressive correction of the iCa to maintain 0.95 mmol/L or higher within 24 hours of admission may improve short-term outcomes.

Level of evidence

Therapeutic/care management, level III.

Impact of Transfused Citrate on Pathophysiology in Massive Transfusion

This narrative review article seeks to highlight the effects of citrate on physiology during massive transfusion of the bleeding patient.

DATA SOURCES

A limited library of curated articles was created using search terms including "citrate intoxication," "citrate massive transfusion," "citrate pharmacokinetics," "hypocalcemia of trauma," "citrate phosphate dextrose," and "hypocalcemia in massive transfusion." Review articles, as well as prospective and retrospective studies were selected based on their relevance for inclusion in this review.

STUDY SELECTION

Given the limited number of relevant studies, studies were reviewed and included if they were written in English. This is not a systematic review nor a meta-analysis.

DATA EXTRACTION AND SYNTHESIS

As this is not a meta-analysis, new statistical analyses were not performed. Relevant data were summarized in the body of the text.

CONCLUSIONS

The physiologic effects of citrate independent of hypocalcemia are poorly understood. While a healthy individual can rapidly clear the citrate in a unit of blood (either through the citric acid cycle or direct excretion in urine), the physiology of hemorrhagic shock can lead to decreased clearance and prolonged circulation of citrate. The so-called "Diamond of Death" of bleeding-coagulopathy, acidemia, hypothermia, and hypocalcemia-has a dynamic interaction with citrate that can lead to a death spiral. Hypothermia and acidemia both decrease citrate clearance while circulating citrate decreases thrombin generation and platelet function, leading to ionized hypocalcemia, coagulopathy, and need for further transfusion resulting in a new citrate load. Whole blood transfusion typically requires lower volumes of transfused product than component therapy alone, resulting in a lower citrate burden. Efforts should be made to limit the amount of citrate infused into a patient in hemorrhagic shock while simultaneously addressing the induced hypocalcemia.

Traumatic hemorrhage and chain of survival

Trauma is the number one cause of death among Americans between the ages of 1 and 46 years, costing more than $670 billion a year. Following death related to central nervous system injury, hemorrhage accounts for the majority of remaining traumatic fatalities. Among those with severe trauma that reach the hospital alive, many may survive if the hemorrhage and traumatic injuries are diagnosed and adequately treated in a timely fashion. This article aims to review the recent advances in pathophysiology management following a traumatic hemorrhage as well as the role of diagnostic imaging in identifying the source of hemorrhage. The principles of damage control resuscitation and damage control surgery are also discussed. The chain of survival for severe hemorrhage begins with primary prevention; however, once trauma has occurred, prehospital interventions and hospital care with early injury recognition, resuscitation, definitive hemostasis, and achieving endpoints of resuscitation become paramount. An algorithm is proposed for achieving these goals in a timely fashion as the median time from onset of hemorrhagic shock and death is 2 h.

Hypocalcemia in Trauma is Determined by the Number of Units Transfused, Not Whole Blood Versus Component Therapy

INTRODUCTION

Blood component resuscitation is associated with hypocalcemia (HC) (iCal <0.9 mmol/L) that contributes to coagulopathy and death in trauma patients. It is unknown whether or not whole blood (WB) resuscitation helps mitigate the risk of HC in trauma patients. We hypothesized that calcium homeostasis is maintained and mortality improved in patients who only receive WB.

MATERIALS AND METHODS

This is a retrospective review of all adult trauma patients who received WB from July 2018 to December 2020. Variables included transfusions, ionized calcium levels, and calcium replacement. Patients were characterized as follows based on blood products received: WB or WB with other blood components. Groups were compared with respect to HC, correction of HC, 24 h, and inpatient mortality.

RESULTS

Two hundred twenty-three patients received WB and met the inclusion criteria. 107 (48%) received WB only. HC occurred in 13% of patients who received more than one WB unit compared to 29% of WB and other blood component patients (P = 0.02). WB patients received less calcium replacement (median 250 mg versus 2000 mg, P < 0.01). HC and total units transfused within 4 h were associated with mortality in the adjusted model. HC significantly increased after 5 units of blood products were transfused, regardless of product type. WB was not protective against HC.

CONCLUSIONS

HC and failure to correct HC are significant risk factors for mortality in trauma. Resuscitations with WB only and WB in combination with other blood components are associated with HC especially when more than 5 units of any blood product are transfused. Calcium supplementation should be prioritized in any large volume transfusion, regardless of blood product type.

Biochemical disturbance in damage control resuscitation: mechanisms, management and prognostic utility

PURPOSE OF REVIEW

With advances in resuscitative techniques, trauma patients are surviving increasingly severe injuries and physiological insult. Timely recognition of futility remains important in terms of patient dignity and resource preservation yet is increasingly challenging in the face of these advances. The understanding of biochemical derangement from pathophysiological processes of trauma and iatrogenic effects of resuscitation has expanded recently.

RECENT FINDINGS

Acidosis and hypocalcaemia have been recognized as important contributors to mortality among trauma patients. Although less well recognized and studied, critical injury and high blood product volume resuscitation render patients vulnerable to life-threatening hyperkalaemia. The methods of correcting disruptions to acid-base and electrolyte homeostasis during damage control resuscitation have changed little recently and often rely on evidence from undifferentiated populations. Biochemical disturbances have value as ancillary predictors of futility in trauma resuscitation.

SUMMARY

These findings will contribute to a greater understanding among anaesthesiologists of the causative mechanisms and effects of biochemical derangement after severe injury and aid them in the delivery of well tolerated and effective damage control resuscitation. Gaps in the evidence base are highlighted to encourage future work.

Surgical Science and the Evolution of Critical Care Medicine

Surgical science has driven innovation and inquiry across adult and pediatric disciplines that provide critical care regardless of location. Surgically originated but broadly applicable knowledge has been globally shared within the pages Critical Care Medicine over the last 50 years.

ANTIOXIDANT-PROOXIDANT BALANCE OF THE KIDNEYS IN RATS OF DIFFERENT AGES UNDER CONDITIONS OF EXPERIMENTAL CRANIOSKELETAL TRAUMA

OBJECTIVE

The aim: To determine the peculiarities of the antioxidant-prooxidant balance in the kidney of rats of different ages under conditions of experimental cranioskeletal trauma (CST).

PATIENTS AND METHODS

Materials and methods: The experiments involved 147 male white Wistar rats of different age groups. The first experimental group included immature animals aged 100-120 days. The second group included sexually mature animals aged 6-8 months. The third group included old animals aged 19-23 months. In all experimental groups, CST was modelled under thiopental-sodium anaesthesia. The control groups of rats was only injected with thiopental-sodium anaesthesia. The animals were withdrawn from the experiments under anaesthesia after 1, 3, 7, 14, 21 and 28 days by total bleeding from the heart. The content of reagents to thiobarbituric acid and catalase activity was determined in a 10 % kidney homogenate extract, and the antioxidant-prooxidant index (API) was calculated from the ratio of these two parameters.

RESULTS

Results: As a result of the application of CST in rats of different age groups, a decrease in the value of renal API was observed with a maximum in immature rats - after 7 days, in mature and old rats - after 14 days. By day 28, the index increased in all experimental groups, but did not reach the control level. The degree of decrease in renal API in old rats under the influence of CCT was significantly higher than in other experimental groups. In immature rats, the impairment of renal API after the application of CST was less, indicating higher reserve capacity of the renal antioxidant defence system in this age group of rats.

CONCLUSION

Conclusions: Simulation of CST in rats of different age groups is accompanied by a decrease in the value of API, which by day 28 does not reach the control level in any of the experimental groups. The degree of decrease in renal API value statistically significantly increases with increasing age of rats at all times of the post-traumatic period.

Change in outcomes for trauma patients over time: Two decades of a state trauma system

BACKGROUND

Trauma center mortality rates are benchmarked to expected rates of death based on patient and injury characteristics. The expected mortality rate is recalculated from pooled outcomes across a trauma system each year, obscuring system-level change across years. We hypothesized that risk-adjusted mortality would decrease over time within a state-wide trauma system.

METHODS

We identified adult trauma patients presenting to Level I and II Pennsylvania trauma centers, 1999-2018, using the Pennsylvania Trauma Outcomes Study. Multivariable logistic regression generated risk-adjusted models for mortality in all patients, and in key subgroups: penetrating torso injury, blunt multisystem trauma, and patients presenting in shock.

RESULTS

Of 162,646 included patients, 123,518 (76.1%) were white and 108,936 (67.0%) were male. The median age was 49 (interquartile range [IQR] 29-70), median injury severity score was 16 (IQR 10-24), and 87.5% of injuries were blunt. Overall, 9.9% of patients died, and compared to 1999, no year had significantly higher adjusted odds of mortality. Overall mortality was significantly lower in 2007-2009 and 2011-2018. Of patients with blunt, multisystem injuries, 17.7% died, and adjusted mortality improved over time. Mortality rates were 24.9% for penetrating torso injury, and 56.9% for shock, with no significant change. Mortality improved for patients with ISS < 25, but not for the most severely injured.

CONCLUSIONS

Over 20 years, Pennsylvania trauma centers demonstrated improved risk-adjusted mortality rates overall, but improvement remains lacking in high-risk groups despite numerous innovations and practice changes in this time period. Identifying change over time can help guide focus to these critical gaps.

Pre-hospital blood products and calcium replacement protocols in UK critical care services: A survey of current practice

Introduction

In the United Kingdom, prehospital blood products are increasingly carried for the early resuscitation of hypovolaemia in patients who are shocked or in cardiac arrest. There is an association between hypocalcaemia and mortality in trauma patients, but no current national guidelines on the timing or dose of calcium replacement exist. The objective of this study was to establish the availability of prehospital blood products, and the current calcium replacement protocols used by UK prehospital services.

Methods

A cross sectional survey of all UK air ambulances and additional prehospital critical care organisations was conducted in April-May 2022 via an on-line questionnaire. The survey asked 11 questions about availability of prehospital blood products, calcium replacement for patients requiring prehospital blood products, and the use of point of care testing.

Results

There was a 100% response rate with 20/22 UK air ambulances carrying blood products and five additional prehospital services identified. There were 15 different combinations of prehospital blood products. 23/25 services had a standard operating procedure for the replacement of calcium. This was recommended before any blood product administration in 5 services (22%), during or after the 1st unit in 5 services (22%), during or after the 2nd unit in 6 services (26%) and during or after the 4th unit in 7 services (30%). Only six services carried point of care testing and no services routinely used this to measure calcium levels in patients requiring prehospital blood products.

Conclusion

In 2022, 91% of UK air ambulances carry prehospital blood products and there is significant variation between services in the combination of blood products provided. There is no consensus on the timing or dose of calcium replacement. Further prospective research should examine the association between traumatic bleeding and ionized calcium levels before and during blood product transfusion in order to produce more robust guidelines for routine calcium replacement.

Trauma-related electrolyte disturbances: From resuscitation to rhabdomyolysis

Traumatic injury results in drastic changes to a patient's normal physiology. The hormonal stress response, as well as some treatment strategies, lead to significant disruptions in electrolyte homeostasis that are important for clinicians to understand. In addition, advances in fluid resuscitation and modern transfusion practices have led to their own unique set of consequences, which we are just beginning to appreciate. Special attention is placed on rhabdomyolysis, as this distinct entity represents an extreme example of injury induced electrolyte derangements. This review describes the physiologic response to trauma and highlights some of the important electrolyte abnormalities that can be encountered while caring for the injured patient.

Hypocalcemia as a predictor of mortality and transfusion. A scoping review of hypocalcemia in trauma and hemostatic resuscitation

BACKGROUND

Calcium plays an essential role in physiologic processes, including trauma's "Lethal Diamond." Thus, inadequate serum calcium in trauma patients exacerbates the effects of hemorrhagic shock secondary to traumatic injury and subsequently poorer outcomes compared to those with adequate calcium levels. Evidence to date supports the consideration of calcium derangements when assessing the risk of mortality and the need for blood product transfusion in trauma patients. This review aims to further elucidate the predictive strength of this association for future treatment guidelines and clinical trials.

METHODS

Publications were collected on the relationship between i-Ca and the outcomes of traumatic injuries from PubMed, Web of Science, and CINAHL. Manuscripts were reviewed to select for English language studies. Hypocalcemia was defined as i-Ca <1.2 mmol/L.

RESULTS

Using PRISMA guidelines, we reviewed 300 studies, 7 of which met our inclusion criteria. Five papers showed an association between hypocalcemia and mortality.

CONCLUSIONS

In adult trauma patients, there has been an association seen between hypocalcemia, mortality, and the need for increased blood product transfusions. It is possible we are now seeing an association between low calcium levels prior to blood product administration and an increased risk for mortality and need for transfusion. Hypocalcemia may serve as a biomarker to show these needs. Therefore, hypocalcemia could potentially be used as an independent predictor for multiple transfusions such that ionized calcium measurements could be used predictively, allowing faster administration of blood products.

Dimethyl malonate slows succinate accumulation and preserves cardiac function in a swine model of hemorrhagic shock

BACKGROUND

Succinate (SI) is a citric acid cycle metabolite that accumulates in tissues during hemorrhagic shock (HS) due to electron transport chain uncoupling. Dimethyl malonate (DMM) is a competitive inhibitor of SI dehydrogenase, which has been shown to reduce SI accumulation and protect against reperfusion injury. Whether DMM can be therapeutic after severe HS is unknown. We hypothesized that DMM would prevent SI buildup during resuscitation (RES) in a swine model of HS, leading to better physiological recovery after RES.

METHODS

The carotid arteries of Yorkshire pigs were cannulated with a 5-Fr catheter. After placement of a Swan-Ganz catheter and femoral arterial line, the carotid catheters were opened and the animals were exsanguinated to a mean arterial pressure (MAP) of 45 mm. After 30 minutes in the shock state, the animals were resuscitated to a MAP of 60 mm using lactated ringers. A MAP above 60 mm was maintained throughout RES. One group received 10 mg/kg of DMM (n = 6), while the control received sham injections (n = 6). The primary end-point was SI levels. Secondary end-points included cardiac function and lactate.

RESULTS

Succinate levels increased from baseline to the 20-minute RES point in control, while the DMM cohort remained unchanged. The DMM group required less intravenous fluid to maintain a MAP above 60 (450.0 vs. 229.0 mL; p = 0.01). The DMM group had higher pulmonary capillary wedge pressure at the 20-minute and 40-minute RES points. The DMM group had better recovery of cardiac output and index during RES, while the control had no improvement. While lactate levels were similar, DMM may lead to increased ionized calcium levels.

DISCUSSION

Dimethyl malonate slows SI accumulation during HS and helps preserve cardiac filling pressures and function during RES. In addition, DMM may protect against depletion of ionized calcium. Dimethyl malonate may have therapeutic potential during HS.

Trauma-induced hypocalcemia

BACKGROUND

Trauma-induced hypocalcemia is an underappreciated complication of severe injury but is well known to result in the derangement of an array of physiological regulatory mechanisms. Existing literature provides a compelling link between hypocalcemia and worse trauma-induced coagulopathy and increased mortality after injury.

STUDY DESIGN AND METHODS

This narrative review evaluates available data related to the risk factors, mechanisms, and treatment of hypocalcemia after severe injury. The authors did not perform a systemic review or meta-analysis.

RESULTS AND DISCUSSION

The interplay of acidosis, hypothermia, and coagulopathy with hypocalcemia potentiates the bloody vicious cycle of hemorrhagic shock which has been the paradigm of trauma resuscitation for over half a century. However, current screening and treatment of postinjury hypocalcemia are relegated to a secondary consideration in trauma resuscitation. We conclude calcium supplementation should be a primary tier intervention for life-threatening injury.

Association between calcium administration and outcomes during adult cardiopulmonary resuscitation at the emergency department

OBJECTIVES

Calcium administration during cardiac arrest is limited in some circumstances, mainly due to lack of consistent evidence. This study aims to investigate whether calcium therapy administered during cardiac arrest at the Emergency Department is associated with good outcomes, including the probability of return of spontaneous circulation (ROSC), survival to hospital admission, survival to hospital discharge, and favorable neurological outcome at discharge.

METHODS

We retrospectively reviewed 599 consecutive adult cardiac arrest events between 2016 and 2018. The primary outcome was the ROSC rate. Secondary outcomes included survival to hospital admission, survival to hospital discharge, and favorable neurologic outcome at hospital discharge. Multivariable logistic regression with inverse probability of treatment weighting was analyzed to examine the association between calcium administration and outcomes.

RESULTS

Of 599 events, calcium was administered in 72 (12%) cases. The use of calcium during cardiopulmonary resuscitation (CPR) after adjusting for confounding factors was not associated with any better outcomes, including ROSC (adjusted odds ratio (aOR) 0.53, 95% confidence interval [CI] 0.24-1.17), survival to hospital admission (aOR 1.07, 95% CI 0.47-2.41), survival to hospital discharge (aOR 1.93, 95% CI 0.43-8.56), and favorable neurological outcome (aOR 6.60, 95% CI 0.72-60.74). Besides, calcium use in traumatic cardiac arrest patients was associated with unfavorable outcomes, including ROSC (aOR 0.02, 95% CI 0.00-0.09) and survival to hospital admission (aOR 0.16, 95% CI 0.03-0.84).

CONCLUSION

The use of calcium during an adult cardiac arrest was not associated with better outcomes. Although associations drawn from this study did not indicate the causality, given calcium during CPR was linked to poorer outcomes in traumatic cardiac arrest patients, including ROSC and survival to hospital admission.

Prehospital Plasma Transfusion: What Does the Literature Show?

Background

Early initiation of blood products transfusion after injury has been associated with improved patient outcomes following traumatic injury. The ability to transfuse patients' plasma in the prehospital setting provides a prime opportunity to begin resuscitation with blood products earlier and with a more balanced plasma: RBC ratio than what has traditionally been done. Published studies on the use of prehospital plasma show a complex relationship between its use and improved survival.

Summary

Examination of the literature shows that there may be a mortality benefit from the use of prehospital plasma, but that it may be limited to certain subgroups of trauma patients. The likelihood of realizing these survival benefits appears to be predicted by several factors including the type of injury, length of transport time, presence of traumatic brain injury, and total number of blood products transfused, whether the patient required only a few products or a massive transfusion. When taken as a whole the evidence appears to show that prehospital plasma may have a mortality benefit that is most clearly demonstrated in patients with blunt injuries, moderate transfusion requirements, traumatic brain injury, and/or transport time greater than 20 min, as well as those who demonstrate a certain cytokine expression profile.

Key Messages

The evidence suggests that a targeted use of prehospital plasma will most likely maximize the benefits from the use of this limited resource. It is also possible that prehospital plasma may best be provided through whole blood as survival benefits were greatest in patients who received both prehospital plasma and RBCs.

Staying on target: Maintaining a balanced resuscitation during damage-control resuscitation improves survival

BACKGROUND

Damage-control resuscitation (DCR) improves survival in severely bleeding patients. However, deviating from balanced transfusion ratios during a resuscitation may limit this benefit. We hypothesized that maintaining a balanced resuscitation during DCR is independently associated with improved survival.

METHODS

This was a secondary analysis of the Prospective Observational Multicenter Major Trauma Transfusion (PROMMTT) study. Patients receiving >3 U of packed red blood cells (PRBCs) during any 1-hour period over the first 6 hours and surviving beyond 30 minutes were included. Linear regression assessed the effect of percent time in a high-ratio range on 24-hour survival. We identified an optimal ratio and percent of time above the target ratio threshold by Youden's index. We compared patients with a 6-hour ratio above the target and above the percent time threshold (on-target) with all others (off-target). Kaplan-Meier analysis assessed the combined effect of blood product ratio and percent time over the target ratio on 24-hour and 30-day survival. Multivariable logistic regression identified factors independently associated with 24-hour and 30-day survival.

RESULTS

Of 1,245 PROMMTT patients, 524 met the inclusion criteria. Optimal targets were plasma/PRBC and platelet/PRBC of 0.75 (3:4) and ≥40% time spent over this threshold. For plasma/PRBC, on-target (n = 213) versus off-target (n = 311) patients were younger (median, 31 years; interquartile range, [22-50] vs. 40 [25-54]; p = 0.002) with similar injury burdens and presenting physiology. Similar patterns were observed for platelet/PRBC on-target (n = 116) and off-target (n = 408) patients. After adjusting for differences, on-target plasma/PRBC patients had significantly improved 24-hour (odds ratio, 2.25; 95% confidence interval, 1.20-4.23) and 30-day (odds ratio, 1.97; 95% confidence interval, 1.14-3.41) survival, while on-target platelet/PRBC patients did not.

CONCLUSION

Maintaining a high ratio of plasma/PRBC during DCR is independently associated with improved survival. Performance improvement efforts and prospective studies should capture time spent in a high-ratio range.

LEVEL OF EVIDENCE

Epidemiologic/prognostic study, level II; Therapeutic, level IV.

Hypofibrinogenaemia and hypocalcaemia in adult trauma patients receiving pre-hospital packed red blood cell transfusions: Potential for supplementary pre-hospital therapeutic interventions

OBJECTIVE

To report the arrival ionised calcium (iCa) and fibrinogen concentrations in trauma patients treated with packed red blood cells by the road-based high-acuity response units of a metropolitan ambulance service.

METHODS

A retrospective review of trauma patients treated with packed red blood cells by high-acuity response units between January 2012 and December 2016. Patients were identified from databases at southeast Queensland adult trauma centres, Pathology Queensland Central Transfusion Laboratory, Gold Coast University Hospital blood bank and the Queensland Ambulance Service. Patient characteristics, results of laboratory tests within 30 min of ED arrival were analysed.

RESULTS

A total of 164 cases were analysed. The median injury severity score was 33.5 (interquartile range 22-41), with blunt trauma the commonest mechanism of injury (n = 128, 78.0%). Fifty-eight of the 117 patients (24.4%) with fibrinogen measured had a fibrinogen concentration ≤1.5 g/L; 79 of the 123 patients (64.2%) with an international normalised ratio (INR) measurement had an INR >1.2; 97 of 148 patients (63.8%) with an iCa measured, had an iCa below the Pathology Queensland reference range of 1.15-1.32 mmol/L. Arrival fibrinogen concentration ≤1.5 g/L and arrival iCa ≤1.00 were associated with in-hospital mortality with odds ratio 11.90 (95% confidence interval 4.50-31.65) and odds ratio 4.97 (95% confidence interval 1.42-17.47), respectively.

CONCLUSIONS

Hypocalcaemia and hypofibrinogenaemia on ED arrival were common in this cohort. Future work should evaluate whether outcomes improve by correction of these deficits during the pre-hospital phase of trauma care.

Dysmagnesemia Is the Most Common Disturbance of the Calcium-Magnesium-Phosphorous Balance among Older Hospitalized People in Warsaw

The elderly are at great risk of developing life-threatening disturbances in calcium–magnesium–phosphate homeostasis because of comorbidities, long-term medication use, and dietary deficiencies, but it is still not known how often they occur in this group of patients. This study aimed to assess the prevalence of these disturbances in a group of hospitalized patients over 65 years of age according to age and sex. The study was conducted between January 2018 and September 2020 at the Central Clinical Hospital in Warsaw. A total of 66,450 calcium, magnesium, phosphate, and vitamin D concentration results were included in the analysis. Dysmagnesemia was present in 33% of the calcium results, dyscalcemia, dysphosphatemia, and dysvitaminosis D—in 23.5%, 26%, and 70% of the results, respectively. The magnesium concentration was found to be age-dependent, and older people were found to be at higher risk of developing abnormal magnesium concentrations (p < 0.001). Sex influenced the occurrence of abnormal magnesium (p < 0.001), vitamin D (p < 0.001), and calcium (p < 0.00001) concentrations, with hypercalcemia and hypervitaminosis D disorders being significantly more common in women (p < 0.0001). In conclusion, disorders of the calcium–magnesium–phosphate metabolism are common in hospitalized patients over 65 years of age, and the concentrations of these substances should be routinely monitored in this group.

Massive transfusions and severe hypocalcemia: An opportunity for monitoring and supplementation guidelines

BACKGROUND

Massive transfusion protocols (MTPs) are associated with severe hypocalcemia, contributing to coagulopathy and mortality in severely injured patients. Severity of hypocalcemia following massive transfusion activation and appropriate treatment strategies remain undefined.

STUDY DESIGN AND METHODS

This was a retrospective study of all MTP activations in adult trauma patients at a Level 1 trauma center between August 2016 and September 2017. Units of blood products transfused, ionized calcium levels, and amount of calcium supplementation administered were recorded. Primary outcomes were ionized calcium levels and the incidence of severe ionized hypocalcemia (iCa ≤1.0 mmol/L) in relation to the volume of blood products transfused.

RESULTS

Seventy-one patients had an MTP activated during the study period. The median amount of packed red blood cells (PRBCs) transfused was 10 units (range 1-52). A total of 42 (59.1%) patients had periods of severe hypocalcemia. Patients receiving 13 or more units of PRBC had a greater prevalence of hypocalcemia with 83.3% having at least one measured ionized calcium ≤1.0 mmoL/L (p = .001). The number of ionized calcium levels checked and the amount of supplemental calcium given in patients who experienced hypocalcemia varied considerably.

DISCUSSION

Severe hypocalcemia commonly occurs during MTP activations and correlates with the number of packed red blood cells transfused. Monitoring of ionized calcium and amount of calcium supplementation administered is widely variable. Standardized protocols for recognition and management of severe hypocalcemia during massive transfusions may improve outcomes.

Does Gender Matter: A Multi-Institutional Analysis of Viscoelastic Profiles for 1565 Trauma Patients With Severe Hemorrhage

BACKGROUND

Viscoelastic tests including thromboelastography (TEG) and rotational thromboelastometry (ROTEM) are being used in patients with severe hemorrhage at trauma centers to guide resuscitation. Several recent studies demonstrated hypercoagulability in female trauma patients that was associated with a survival advantage. The objective of our study was to elucidate the effects of gender differences in TEG/ROTEM values on survival in trauma patients with severe hemorrhage.

METHODS

A retrospective review of consecutive adult patients receiving massive transfusion protocol (MTP) at 7 Level I trauma centers was performed from 2013 to 2018. Data were stratified by gender and then further examined by TEG or ROTEM parameters. Results were analyzed using univariate and multi-variate analyses.

RESULTS

A total of 1565 patients were included with 70.9% male gender (n = 1110/1565). Female trauma patients were older than male patients (43.5 ± .9 vs 41.1 ± .6 years, P = .01). On TEG, females had longer reaction times (6.1 ± .9 min vs 4.8 ± .2 min, P = .03), increased alpha angle (68.6 ± .8 vs 65.7 ± .4, P < .001), and higher maximum amplitude (59.8 ± .8 vs 56.3 ± .4, P < .001). On ROTEM, females had significantly longer clot time (99.2 ± 13.7 vs 75.1 ± 2.6 sec, P = .09) and clot formation time (153.6 ± 10.6 sec vs 106.9 ± 3.8 sec, P < .001). When comparing by gender, no difference for in-hospital mortality was found for patients in the TEG or ROTEM group (P > .05). Multivariate analysis showed no survival difference for female patients (OR 1.11, 95% CI .83-1.50, P = .48).

CONCLUSIONS

Although a difference between male and females was found on TEG/ROTEM for certain clotting parameters, no difference in mortality was observed. Prospective multi-institutional studies are needed.

Volume of packed red blood cells and fresh frozen plasma is associated with intraoperative hypocalcaemia during large volume intraoperative transfusion

BACKGROUND

Severe hypocalcaemia is associated with increased transfusion in the trauma population. Furthermore, trauma patients developing severe hypocalcaemia have higher mortality and coagulopathy. Electrolyte abnormalities associated with massive transfusion have been less studied in the surgical population. Here, we tested the primary hypothesis that volume of packed red blood cells and fresh frozen plasma transfused intraoperatively is associated with lower nadir ionised calcium in the surgical population receiving massive resuscitation.

METHODS

We performed a retrospective observational study at an academic quaternary care centre to characterise hypocalcaemia following large volume (4 or more units packed red blood cells) intraoperative transfusion. We used multivariable linear regression to assess if volume of transfusion with packed red blood cells and fresh frozen plasma were independently associated with a lower ionised calcium. We then used multivariable logistic regressions to assess the association between ionised calcium and transfusion with: (i) mortality, (ii) acute kidney injury, and (iii) postoperative coagulopathy.

RESULTS

Hypocalcaemia following large volume resuscitation in the operating room is a very frequent occurrence (70% of cases). After controlling for demographic variables and intraoperative variables, the volume transfused intraoperative was independently associated with hypocalcaemia on multivariable linear regression. Hypocalcaemia, intraoperative transfusion of packed red blood cells, and intraoperative transfusion of fresh frozen plasma were not shown to be associated with clinical outcomes.

CONCLUSIONS

Hypocalcaemia was associated with increased transfusion volume in this single-centre study. Unlike the trauma population, hypocalcaemia was not associated with increased mortality during surgical care. Our findings suggest that despite improved practice patterns of calcium supplementation, intraoperative hypocalcaemia occurs with relatively high frequency following large volume intraoperative transfusion.

A retrospective analysis of calcium levels in pediatric trauma patients

Traumatic injury is a major cause of morbidity and mortality in pediatric patients. Hemorrhage is a known but treatable component of these outcomes. Evidence exists that major trauma patients are at high risk for hypocalcemia but the rate of pediatric occurrence is not documented. The purpose of this study was to determine the incidence of hypocalcemia in pediatric trauma patients, as well as to investigate any correlation between hypocalcemia and the need for transfusion and operative intervention. After IRB approval a retrospective analysis was conducted of all pediatric trauma patients seen in our Adult Level One, Pediatric Level Two trauma center. Significance testing for mortality was performed using Pearson's χ2 test. For the remaining numeric variables, association was determined one-way analysis of variance (when comparing all classes) or Welch's two-sample t-test (when comparing subsets based on calcium or mortality). In any event, significance was determined using α=0.05. A total of 2,928 patients were identified, 1623 were excluded, primarily due to incomplete data. Patients were predominantly male following blunt trauma. Initial calcium levels were 8.73 mg/dL, 95% CI [4-10.9] and 8.97 mg/dL, 95% CI [6.42-13.1] when correcting for albumin levels. Acute declines were noted when comparing initial and corrected serum calcium levels in patients requiring transfusion (7.99 mg/dL and 8.72 mg/dL) and operative intervention (8.54 mg/dL and 8.91 mg/dL). 456 (34.9%) patients required operative intervention, 138 (10.6%) required transfusion and 29 (2.2%) required massive transfusion. Patients in our cohort arrived with calcium values on the low end of normal, with a trend towards hypocalcemia if operative intervention or blood transfusion was required. This has been previously associated with increased mortality. Patients requiring operative intervention and transfusion are at increased risk for hypocalcemia and recognition of this potential is key for improved outcomes.

Hypocalcemia in Military Casualties From Point of Injury to Surgical Teams in Afghanistan

INTRODUCTION

Hypocalcemia is a known sequela of citrated blood product transfusion. Civilian data suggest hypocalcemia on hospital admission is associated with worse outcomes. Initial calcium levels in military casualties have not previously been analyzed. The objective of this retrospective review aimed to assess the initial calcium levels in military trauma casualties at different Forward Surgical Teams (FST) locations in Afghanistan and describe the effects of prehospital blood product administration on arrival calcium levels.

MATERIALS AND METHODS

This is a retrospective cohort analysis of military casualties arriving from point of injury to one of two FSTs in Afghanistan from August 2018 to February 2019 split into four locations. The primary outcome was incidence of hypocalcemia (ionized calcium < 1.20 mmol/L).

RESULTS

There were 101 patients included; 55 (54.5%) experienced hypocalcemia on arrival to the FST with a mean calcium of 1.16 mmol/L (95% confidence interval [CI], 1.14 to 1.18). The predominant mechanism of injury consisted of blast patterns, 46 (45.5%), which conferred an increased risk of hypocalcemia compared to all other patterns of injury (odds ratio = 2.42, P = .042). Thirty-eight (37.6%) patients required blood product transfusion. Thirty-three (86.8%) of the patients requiring blood product transfusion were hypocalcemic on arrival. Mean initial calcium of patients receiving blood product was 1.13 mmol/L (95% CI, 1.08 to 1.18), which was significantly lower than those who did not require transfusion (P = .01). Eight (7.9%) of the patients received blood products before arrival, with 6/8 (75%) presenting with hypocalcemia.

CONCLUSIONS

Hypocalcemia develops rapidly in military casualties and is prevalent on admission even before transfusion of citrated blood products. Blast injuries may confer an increased risk of developing hypocalcemia. This data support earlier use of calcium supplementation during resuscitation.

The Use of Whole Blood Transfusion During Non-Traumatic Resuscitation

BACKGROUND

Evidence from military populations showed that resuscitation using whole blood (WB), as opposed to component therapies, may provide additional survival benefits to traumatically injured patients. However, there is a paucity of data available for the use of WB in uninjured patients requiring transfusion. We sought to describe the use of WB in non-trauma patients at Brooke Army Medical Center (BAMC).

MATERIALS AND METHODS

Between January and December 2019, the BAMC ClinComp electronic medical record system was reviewed for all patients admitted to the hospital who received at least one unit of WB during this time period. Patients were sorted based on their primary admission diagnosis. Patients with a primary trauma-based admission were excluded.

RESULTS

One hundred patients were identified who received at least one unit of WB with a primary non-trauma admission diagnosis. Patients, on average, received 1,064 mL (750-2,458 mL) of WB but received higher volumes of component therapy. Obstetric/gynecologic (OBGYN) indications represented the largest percentage of non-trauma patients who received WB (23%), followed by hematologic/oncologic indications (16%).

CONCLUSION

In this retrospective study, WB was most commonly used for OBGYN-associated bleeding. As WB becomes more widespread across the USA for use in traumatically injured patients, it is likely that WB will be more commonly used for non-trauma patients. More outcome data are required to safely expand the indications for WB use beyond trauma.

Successful Management of a Patient with Intraoperative Bleeding of More than 80,000 mL and Usefulness of QTc Monitoring for Calcium Correction

Intraoperative massive bleeding is associated with high rates of mortality and anesthetic management of massive bleeding is challenging because it is necessary to achieve volume resuscitation and electrolyte correction simultaneously during massive transfusion. We report a case of life-threatening bleeding of more than 80,000 mL during liver transplantation in which real-time QTc monitoring was useful for an extremely large amount of calcium administration for treatment of hypocalcemia. A 47-year-old female with a giant liver due to polycystic liver disease was scheduled to undergo liver transplantation. During surgery, life-threatening massive bleeding occurred. The maximum rate of blood loss was approximately 15,000 mL/hr and the total amount of estimated blood loss was 81,600 mL. It was extremely difficult to maintain blood pressure and a risk of cardiac arrest continued due to hypotension. In addition, even though administration of insulin and calcium was performed, electrolyte disturbances of hyperkalemia and hypocalcemia with prolongation of QTc interval occurred. At that time, we visually noticed that the QT interval was shortened in response to bolus calcium administration, and we used the change of real-time QTc interval as a supportive indicator for calcium correction. This monitoring allowed for us to administer calcium at an unusually high rate, by which progression of hypocalcemia was prevented. Levels of hemoglobin and coagulation factors were preserved both by restriction of crystalloid infusion and by a massive transfusion protocol. The patient was extubated without pulmonary edema or cardiac overload and was finally discharged without any sequelae. Intensive and cooperative management for massive transfusion and electrolyte correction using QTc monitoring was considered to be a key for successful management.

Dynamic effects of calcium on in vivo and ex vivo platelet behavior after trauma

BACKGROUND

Mobilization of intra and extracellular calcium is required for platelet activation, aggregation, and degranulation. However, the importance of alterations in the calcium-platelet axis after injury is unknown. We hypothesized that in injured patients, in vivo initial calcium concentrations (pretransfusion) predict ex vivo platelet activation and aggregation, viscoelastic clot strength, and transfusion of blood products. We additionally hypothesized that increasing calcium concentrations ex vivo increases the expression of platelet activation surface receptors and platelet aggregation responses to agonist stimulation in healthy donor blood.

METHODS

Blood samples were collected from 538 trauma patients on arrival to the emergency department. Standard assays (including calcium), platelet aggregometry (PA) and thromboelastometry (ROTEM) were performed. In PA, platelet activation (prestimulation impedance [Ω]) and aggregation responses to agonist stimulation (area under the aggregation curve [AUC]) with adenosine diphosphate (ADP), thrombin receptor-activating peptide, arachidonic acid (AA), and collagen (COL) were measured. Multivariable regression tested the associations of calcium with PA, ROTEM, and transfusions. To further examine the calcium-platelet axis, calcium was titrated in healthy blood. Platelet aggregometry and ROTEM were performed, and expression of platelet glycoprotein IIb/IIIa and P-selectin was measured by flow cytometry.

RESULTS

The patients were moderately injured with normal calcium and platelet counts. Higher calcium on arrival (pretransfusion) was independently associated with increased platelet activation (prestimulation, Ω; p < 0.001), aggregation (ADP-stimulated, AUC; p = 0.002; thrombin receptor-activating peptide-stimulated, AUC; p = 0.038), and clot strength (ROTEM max clot firmness; p < 0.001), and inversely associated with 24-hour transfusions of blood, plasma, and platelets (all p < 0.005). Up-titrating calcium in healthy blood increased platelet activation (prestimulation, Ω; p < 0.001), aggregation (ADP, AA, COL-stimulated AUCs; p < 0.050), and expression of P-selectin (p = 0.003).

CONCLUSION

Initial calcium concentrations (pretransfusion) are independently associated with platelet activation, aggregation, clot-strength, and transfusions after injury. These changes may be mediated by calcium driven expression of surface receptors necessary for platelet activation and aggregation. However, the therapeutic benefit of early, empiric calcium repletion in trauma patients remains undefined.

LEVEL OF EVIDENCE

Prognostic, level V.

Hypocalcemia in trauma patients: A systematic review

BACKGROUND

During hemorrhagic shock and subsequent resuscitation, pathways reliant upon calcium such as platelet function, intrinsic and extrinsic hemostasis, and cardiac contractility are disrupted. The objective of this systematic review was to examine current literature for associations between pretransfusion, admission ionized hypocalcemia, and composite outcomes including mortality, blood transfusion requirements, and coagulopathy in adult trauma patients.

METHODS

This review was reported using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist. We searched Ovid MEDLINE and grey literature from database inception till May 3, 2020. Case series and reports were excluded. Reference lists of appraised studies were also screened for articles that the aforementioned databases might not have captured. The Newcastle-Ottawa Scale was used to assess study quality.

RESULTS

A total of 585 abstracts were screened through database searching and alternative sources. Six unique full-text studies were reviewed, of which three were excluded. Admission ionized hypocalcemia was present in up to 56.2% of the population in studies included in this review. Admission ionized hypocalcemia was also associated with increased mortality in all three studies, with increased blood transfusion requirements in two studies, and with coagulopathy in one study.

CONCLUSION

Hypocalcemia is a common finding in shocked trauma patients. While an association between admission ionized hypocalcemia and mortality, blood transfusion requirements, and coagulopathy has been identified, further prospective trials are essential to corroborating this association.

LEVEL OF EVIDENCE

Systematic review, level III.

Hemostatic defects in massive transfusion: an update and treatment recommendations

INTRODUCTION

Acute hemorrhage is a global healthcare issue, and remains the leading preventable cause of death in trauma. Acute severe hemorrhage can be related to traumatic, peripartum, gastrointestinal, and procedural causes. Hemostatic defects occur early in patients requiring massive transfusion. Early recognition and treatment of hemorrhage and hemostatic defects are required to save lives and to achieve optimal patient outcomes.

AREAS COVERED

This review discusses current evidence and trials aimed at identifying the optimal treatment for hemostatic defects in hemorrhage and massive transfusion. Literature search included PubMed and Embase.

EXPERT OPINION

Patients with acute hemorrhage requiring massive transfusion commonly develop coagulopathy due to specific hemostatic defects, and accurate diagnosis and prompt correction are required for definitive hemorrhage control. Damage control resuscitation and massive transfusion protocols are optimal initial treatment strategies, followed by goal-directed individualized resuscitation using real-time coagulation monitoring. Distinct phenotypes exist in trauma-induced coagulopathy, including 'Bleeding' or 'Thrombotic' phenotypes, and hyperfibrinolysis vs. fibrinolysis shutdown. The trauma 'lethal triad' (hypothermia, coagulopathy, acidosis) has been updated to the 'lethal diamond' (including hypocalcemia). A number of controversies in optimal management exist, including whole blood vs. component therapy, use of factor concentrates vs. blood products, optimal use of tranexamic acid, and prehospital plasma and tranexamic acid administration.

Reperfusion repercussions: A review of the metabolic derangements following resuscitative endovascular balloon occlusion of the aorta

BACKGROUND

Current resuscitative endovascular balloon occlusion of the aorta (REBOA) literature focuses on improving outcomes through careful patient selection, diligent catheter placement, and expeditious definitive hemorrhage control. However, the detection and treatment of post-REBOA ischemia-reperfusion injury (IRI) remains an area for potential improvement. Herein, we provide a review of the metabolic derangements that we have encountered while managing post-REBOA IRI in past swine experiments. We also provide data-driven clinical recommendations to facilitate resuscitation post-REBOA deflation that may be translatable to humans.

METHODS

We retrospectively reviewed the laboratory data from 25 swine across three varying hemorrhagic shock models that were subjected to complete REBOA of either 45 minutes, 60 minutes, or 90 minutes. In each model the balloon was deflated gradually following definitive hemorrhage control. Animals were then subjected to whole blood transfusion and critical care with frequent electrolyte monitoring and treatment of derangements as necessary.

RESULTS

Plasma lactate peaked and pH nadired long after balloon deflation in all swine in the 45-minute, 60-minute, and 90-minute occlusion models (onset of peak lactate, 32.9 ± 6.35 minutes, 38.8 ± 10.55 minutes, and 49.5 ± 6.5 minutes; pH nadir, 4.3 ± 0.72 minutes, 26.9 ± 12.32 minutes, and 42 ± 7.45 minutes after balloon deflation in the 45-, 60-, and 90-minute occlusion models, respectively). All models displayed persistent hypoglycemia for more than an hour following reperfusion (92.1 ± 105.5 minutes, 125 ± 114.9 minutes, and 96 ± 97.8 minutes after balloon deflation in the 45-, 60-, and 90-minute occlusion groups, respectively). Hypocalcemia and hyperkalemia occurred in all three groups, with some animals requiring treatment more than an hour after reperfusion.

CONCLUSION

Metabolic derangements resulting from REBOA use are common and may worsen long after reperfusion despite resuscitation. Vigilance is required to detect and proactively manage REBOA-associated IRI. Maintaining a readily available "deflation kit" of pharmacological agents needed to treat common post-REBOA electrolyte abnormalities may facilitate management.

LEVEL OF EVIDENCE

Level V.